Hello pbr_44,
Welcome to Apple Support Communities!
If you see a closed lens or black screen when you open the Camera app, try these steps:
Make sure that there’s nothing blocking the camera lens. If you’re using a case, try removing it.
Force the app to close, then open the Camera app again.
Restart your device, then open the Camera app again
If you continue to see a closed lens or black screen, take your device to an Apple Store or Authorized Service Provider for more help.
Here are some resources to get you set up for service:
Get your iPhone, iPad, or iPod touch ready for service - Apple Support
iPhone Repair - Official Apple Support
Thank you for using Apple Support Communities.
Enjoy your day!